Sep 10, 2012 2:24 PM

I realized that my left quad is significantly weak compared to my right knee which may be the cause of my knee pain in my left knee. I've been given some quad strengthening exercises but when I actually try to do the strengthening exercises, my knee hurts! I think my quad is very very weak and can barely the exercises. Seems like a circular issue. Quads weak, therefore knee hurts, but quad exercises hurt knee. So, should I still try to do the exercises even though they hurt my knees?

Some of the exercises have been leg lifts which seem ok. But the squats hurt quite a bit.

Squats, especially with weights, can put a lot of stress on your knees. Preferable quad strengthening exercises are done with your leg straight, knee straight. Here are two exercises that I was taught by a physical therapist many years ago and still do regularly:

(1) Lie flat on your back, one leg bent (with foot flat on the floor) and the other straight. Tighten the quad on the straight leg and then lift about 6 to 8 inches off the floor. Work up to 3 sets of 10. Start with no added weight and then add ankle weight in 1/2 lb increments as strength improves.

(2) Same as (1) except start with the straight leg rotated about 45 deg outwards, and keep it in that orientation as you lift the leg.

Some time back, I read a report about quad contractile force being reduced by sub-patellar inflammation. An automatic defense mechanism, apparently. Damien raises a very good question about the reasons for relative differences in quad strength. There could be neurological or circulatory reasons for an underpowered quad, but you write as if this was a fairly recent development, at least one you recently realized when demands were placed on your quad during training.

I will briefly (as possible) recount what I know about weak quads in the active crowd, because I've gone over it many times before.

A well-exercised quad can deliver a weak contraction for reasons other than the one I mentioned above. It's not as simple as how well-exercised or physically robust a portion of muscle is. It's more about whether the entire nervous system, from your brain through your spinal cord, motor neurons, spindle cells and any other neuromuscular component, is in agreement with your will that a muscle should be flexed strongly. Sometimes, your body knows of a vulnerability you may not be consciously aware of. I aim to change that.

Here I usually digress into a discussion about trigger points, and yes, that is exactly what I am going to do now. While it is true that the available physiology on trigger points does not satisfy the need of science to know exactly what they are, why they occur, and how to treat them, I unfortunately must muddle through and make my living dealing with them almost every day, including as a result of my own athletic activities. I succeed, and you can too.

It is possible, for example, for a tiny nodule of hyper-contracted muscle tissue to cause your muscle not to function normally. Think of yourself being pulled across a room by just one hair on your head. It is not that the hair is that strong, but that the discomfort produced by just one hair being pulled compels you to comply.

You can't always feel, or be conscious of a trigger point, but it can have an effect on your nervous system nevertheless. If even a small group of cells in your muscle are not pulling in agreement with the others, it is possible for the entire muscle to appear dysfunctional. In this way it behaves very much like that annoying hair, and is the tail wagging an otherwise very strong dog.

With that metaphor out of the way, I want to assure you that it is very possible that you could have at least one trigger point (probably many) affecting your ability to use that quad. Here is where I post a link to one doctor's account of the dramatic effect a trigger point had on one particular patient.

Rest assured, I see similar results all the time. Apparently, some pressure in the right spot alters the physiology of a trigger point enough to change or correct it, no matter how that physiology operates. There are probably psychological factors too, since having your tissue manipulated by someone you do not like (or someone who makes you nervous) can have the opposite effect. Unless you don't like yourself (lol), I think you may be the ideal candidate for the job!

Humor me and start scanning the quad on your outstretched and supported leg (seated, with a footstool or ottoman will do), for tight string-like fibers in your quad, palpable lumps of any size, or spots that seem overly sensitive when lightly pressed. Of course, almost any part of your quad can hurt if somebody leans on it with an elbow, but I am talking about scanning it for small differences in tissue tension or sensation. Please use your own fingers, and compare with the other leg for reference, if in doubt about what you find. While sticks and rollers are sometimes used proactively to encourage lymphatic flow and circulatory changes, they are often too blunt an instrument for finding and addressing problem trigger points, even though mild ones might respond well to such therapy.

If you find a sore spot, some tolerable pressure on it for several seconds can cause it to release its tension along with the pain. Sometimes pain is felt or released locally, sometimes in another part of the muscle or affected joint, and sometimes in places quite distant, by virtue of a well known but poorly understood effect known as "pain referral." I'm not talking about cutting off the circulation with the object of temporary numbness, but about enough pressure to make a sustainable change, which varies by individual. Once again, you can best determine this by treating it yourself, once you know what to expect.

A sensitive spot that disappears after a reasonable amount of direct pressure, is very likely (or was) a trigger point. As often happens, another may become evident in a different spot, based on the priority your brain applies to pain. The effect can move around like whack-a-mole. It is not so much a "thing," like a tumor, as much as it is a temporary condition. By temporary, I do not mean to exclude them from lasting many years, as they often do. They are temporary when you address them directly with manual therapy and the neuromuscular feedback and/or physiological changes that result. Do nothing, and they can, in extreme cases, persist for a lifetime, even if they recently materialized.

If you find what feels like a tight string-like fiber in your muscle, it is highly unlikely that the entire fiber is the problem. If you feel along this fiber, you should eventually come to a portion of it that is more sensitive than the rest, a micro-spasm that pulls the entire fiber taught. That is also a trigger point, and can be handled the same way. In most cases, there is doubt about exactly which spot or spots are responsible for muscular dysfunction in any given case, but they tend to follow patterns based on the physical vulnerability of certain tissue, usually at the center of a given length of muscle (not including tendonous extensions).

There was a time when I did not believe in trigger points, even though I was in the business of dealing with soft tissue dysfunction. When a relative came back from the hospital with a doctor's instructions to have her husband apply trigger point therapy to control pain, I felt compelled to come up with an explanation. Years of research have clearly defined the existence of this mysterious muscular behavior, and the universal role it plays in athletic performance at all levels. After more than 70 years of medical research, we still don't know enough about them yet (as with many other medical phenomena), but we at least know how to reduce or eliminate their effects in many cases. Fail to address them, and like it or not, you can expect to keep running into the problems they cause, no matter how well-exercised you are. Perhaps, as you may well have found, you may not even be able to exercise at all, until you tackle them head-on.

While there is a lot we do not know about muscular dysfunction, one thing we do know is that tiny amounts of damage, known as micro-tears in the muscle tissue, can lead to the dysfunction of trigger points. This is entirely different from a major injury such as a "muscle tear," in that the effects may be as dramatic as a major injury, even more painful, but can be overcome relatively quickly, even immediately. It is normal for exercising muscle to be constantly in the process of repair from the damage we exercising yahoos continually inflict. It is also quite normal for muscles to shut down in protest when we don't let up. Sure, you can keep piling it on and get used to the pain, but I hope I have shown you a better way to deal with it. Understand, you still may have damage that must heal. Consider this a shot across the bow from your muscles. Listen to their message, but rather than ignore at your peril, and do too much, or too little, you can learn to communicate back.

Thanks everyone. My PT has been doing some trigger point massage on my quad. So far it hasn't gotten any better. Runner's knee - supposedly. I've been off of it for over 2 months now but it doesn't seem like it is getting any better. He told me to go see a sports doc for another diagnosis. He also told me to do some hip abductor exercises for the next 6 weeks or so. I can't seem to locate any sensitive areas in the quad myself but when the PT does massage it, he can seem to find a few. Not sure what to do anymore. I just want to get back into being active!

Sorry to hear of your experience, Sylvia. If it is any consolation, your experience is all too common. However, it is not necessary. While you are certainly getting some medical attention, more hard work needs to be done to make sure the interventions are properly targeted.

To many in the healthcare industry, and as you may have concluded after self-examination, trigger points do not exist. To those who know of them, they are often little more than palpable knots in a muscle. Unfortunately for diagnosticians, they are much more complicated than that. This WebMD article is just a foretaste:

The different states, detectability and tenacity of trigger points are important aspects to keep in mind when hunting them down and treating them.

One TrP can sponsor one or more others, which can be found and treated, but may reappear soon after, since they are being caused by one or more in a different location, perhaps in a different muscle. Another complicating factor is your two months of rest, which can make TrPs more likely when the rested muscles are again challenged.

There is no doubt that TrPs in the medial quad can cause quad weakness and knee pain, which is well-documented. The question is, why would they be there in the first place? Possible causes include:

Sitting for long periods of time, at present or in the past. Also, sitting with a leg crossed over the quad.

Other sleeping, resting or working postures that hold the quads in a shortened or elongated state for long periods of time, or impact circulation.

Inflammation and/or pain under the knee cap, such as chondromalacia or "runner's knee."

Active trigger points in other muscles in the same or related groups of muscles.

Latent, chronic trigger points in the same or other muscles.

Icing or other cold therapies that can cause TrPs in muscles that would otherwise not have them.

Actual damage in the muscle, or scar tissue from poorly healed damage.

Electrolyte or vitamin deficiencies.

Too much or too little hydration.

Too much repetitive motion or stressful exercise.

Bone structure/alignment issues that overwork the muscle(s).

Helpful interventions include:

Stay active. More consistent, gentle activity can be more productive than rest or targeted exercise.

Whether you do or don't have a definitive diagnosis of chondromalacia, patellar tracking disorder or other knee problems, understanding the relationship between muscular dysfunction, repetitive motion, and resulting damage to the knee can prevent it from getting worse.

Scan all muscles for active and latent TrPs in the group that work with or in opposition to the primary suspect.

Use heat therapies instead of cold to relax and stimulate peripheral circulation, or cold only in alternating contrast with heat, finishing with heat.

Take an inventory of injuries both old and new, even in adjoining tissues, that may have had an impact on the current problem. Assess whether they have healed properly, or would benefit from deeper therapies to dissolve and rebuild the injured tissue.

Even when not vigorously exercising, continue to adjust your diet and hydration for recovery. You are healing.

Evaluate for structural imbalances that cause excess motion, such as excessive pronation, which can in turn lead to overuse of certain muscles like the medial quad. Examples are: a short or hypermobile 1st metatarsal on the foot, leg length discrepancies, pelvic asymmetry, etc.

There are other possible factors, but the important point is to trace the dysfunction to the original cause, or risk treating symptoms made fresh daily. It seems like a lot of hard work to explore these possibilities, but it is still less work than dealing with the symptoms for the rest of your life, which is how long TrPs can persist.

Management of chronic pain and/or muscular dysfunction is a primary consumer of the health-care dollar. Over-simplistic understanding of how muscles malfunction, how to treat them, and how important they are to chronic pain, is a major contributor to the overuse of anti-inflammatory, analgesic, and narcotic drugs, as well as surgery.

A strong muscle can become weak in seconds due to the appearance of a single trigger point in the wrong place. Common exercise interventions to strengthen muscles so riddled with trigger points that they appear weak, simply perpetuate them by straining muscles not healthy enough to be used. Ditto for stretching and icing protocols. Conditioning of a muscle is always more successful when the muscle is healthy. The degree of dysfunction determines whether conditioning by stretching or strengthening will instead be counterproductive.

Soft tissue therapies like foam-rolling and massage are only as likely to solve the problem as a hammer is to build a house. They are just tools, which in properly informed hands can succeed - or fail - if the therapy is directed to a symptom and not a cause. When you are lucky you can find the cause quickly; on average it takes a lot of persistence, and if you are unlucky, even skilled work can make things worse.

Regarding persistence, it is difficult to schedule enough work with a therapist to ensure progress without breaking the bank, which is why I advocate self-massage. The only danger with doing it yourself, is the risk of overdoing it, which is why I advocate enough practice to become good at it. The more skilled you are, the less likely you are to give up or to overwork the problem.